Hadwen swain



(No Model.)

H. SWAIN.

THROW-OFF FOR PRINTING PRESSES- No. 373,421. Patented Nov. 15-, 1887.

Witnesses: I I Inz e nto 1';

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UNITED STATES PATENT OFFICE,

HADVVEN SWAIN, OF SAN FRANCISCO, CALIFORNIA.

THROW-OFF FOR PRlNTlNG-PRESSES.

SPECIFICATION forming part of Letters Patent No. 373,421, dated November15, 1887.

Application filed January 21, 1887. Serial No. 225,010. (No model.)

To all whom it may concern:

Be it known that I, HADWEN SWAIN, a citizen of the United States,residing at San Francisco, in the county of San Francisco and State ofCalifornia, have invented certain new and useful Improvements inThrow-Offs for Printing-Presses, of which the following is adescription.

This invention relates to certain improvements in that class of printingpresses in which means are provided for preventing the type from makingan impression when desired; and it consists in certain improvements inthe th row-off mechanism, whereby the same is simplified and renderedmore efficient in operation than heretofore. These objects I obtain .bythe means hereinafter described and illus-' trated in the accompanyingdrawings, in which- Figure 1 represents a side elevation of a press,showing my invention; Fig. 2, a de tached detail view of a portion ofthe throwoff mechanism; Fig. 3, detached detail views of the lever foroperating the throw off mechanism.

The letter A indicates the frame of the printing-press; B, the maindrivingshaft having a wheel, 0, on one end, with a wrist-pin, D,connecting with the pressure-shaft I, mounted in the frame F of the bed,which is pivoted at its lower end to the main frame, as is usual. Thewrist-pin is connected to the shaft by a pressure-rod, G, engaging theeccentric-stud I on the end of the shaft. The rotation of the shaft Btherefore causes the oscillation of the bed-frame, moving the bed andthe form of types it carries to and from the platen a distance governedby the position of the stud I.

The letter D indicates an angular hand-lever which is pivoted to thestud O of the frame conveniently adjacent to the feed-table A, the studbeing the same to which the side arm, 1?, of the inking-roller frame 0is attached. Thelower end of the lever D is forked to receive the rod B,which is pivoted to said lever by means of a pin or bolt, H. The lowerend of the rod B is pivoted at H to the front end of the rocking beam F,which is bifurcated at both ends and is arranged in substantially ahorizontal position, to rock on astud,

H, which is secured to the main frame A, and forming an approximatelycentral bearing for said beam. The rear end of the rocking beam or framehas pivoted to it on a pin, H one end of a connecting-rod, O, the otherend of which is connected to a strap, E, fastened to the eccentric-shaftI. The eccentric-shaft I is held in position by a spring, R, fastened tothe bed frame, by the engagement of said spring with suitable notches ina strap, S, on said shaft.

It will be observed that in the position of the parts shown in thedrawings, which is the position the parts have when impressions are tobe produced, the pivot-pin H of the throwoff devices is coincident or inline with the pivot of the bed-frame F, so that therefore the positionof the eccentric pin I will not be changed by the oscillation of saidframe, and the force of the impression will not be disturbed by themotion of the machine. Security to this end is further insured by theaction of the spring-clip R on the strap S, the form of these parts,however, being such that the rocking of the shaft I is not hindered whenthe impression is to be thrown off by means of the handlever near thefeed-table.

The operation of myinvention is as follows: The lever D is capable of anoscillatory movement, which imparts an upward and down ward movement tothe rod B. This oscillates the rocking beam F, which in turn raises andlowers the connecting-rod C, which, through the strap E, gives a partialrotation to the shaft I and changes the position of the stud, to whichthe pressure-rod O is attached, thereby putting the bed and its forminto position to make or avoid an impression, as desired.

Having thus described my invention, what I desire to secure by LettersPatent is- 1. The oscillating bed-frame and its eccentric shaft, theapproximately horizontal rocking beam centrally pivoted to the mainframe and having its rear end connected by a rod to said shaft, and thepivoted hand-lever connected by a rod to the front end of said rockingbeam, substantially as described.

2. The combination of the oscillating bedframe and its eccentric shaftwith the handlever, the connecting-rods, and the approximatelyhorizontal rocking beam centrally piv- S, in combination with theconnecting-rod G, oted to the main frame, the pivotin the outer therocking beam F, the connecting-rod B, IO end of which beam coincideswith the pivot of and the hand-lever D, all substantially as dethebed-frame when the lever is in position to scribed.

5 allow impressions, substantially as described. HADWEN SWAIN.

3. The pressure-rod G and the bed-frame F, Witnesses: carrying thespringclip R, and the pressure- A, W. OXLEY, shaft I, having a pin, 1,and a notched strap, H. MARSHALL.

